223 results about "Intra mode" patented technology

An example device for decoding video data includes a memory configured to store video data; and a processing system comprising one or more processors implemented in circuitry, the processing system being configured to: generate a prediction block for a current block of video data using a neural network; determine an equivalent intra mode for the prediction block from a set of available intra-prediction modes using decoder-side intra mode derivation (DIMD), the equivalent intra mode representing one of the intra-prediction modes that would generate an intra-prediction block that would best match the prediction block generated using the neural network; decode a residual block for the current block of the video data based on the equivalent intra mode; and combine the prediction block with the residual block to decode the current block of the video data.

A video encoder and video decoder may determine to code a block of video data using a non-directional intra mode. The video encoder and video decoder may determine a secondary transform from a secondary transform set for the block, and perform a transform process on the block of video data using the secondary transform. For non-directional intra prediction modes, the secondary transform set has a first number of transform kernels that is less than a second number of transform kernels in the secondary transform set for other blocks coded using a directional intra mode.

A video coder may code a flag indicating whether or not a neural network (NN)-based intra prediction mode is enabled before coding a decoder side intra mode derivation (DIMD) flag, and code a block of video data based on whether or not the NN-based intra prediction mode is enabled.

Provided is an image decoding method performed by a decoding apparatus, the image decoding method including receiving image information including at least one of decoder-side intra mode derivation (DIMD)-related information or template-based intra mode derivation (TIMD)-related information from a bitstream, deriving an intra prediction mode of a current block on the basis of the at least one of the DIMD-related information or the TIMD-related information, generating prediction samples of the current block on the basis of the intra prediction mode, and generating reconstructed samples of the current block on the basis of the prediction samples of the current block. The image information includes matrix-based intra prediction (MIP) flag information, the DIMD-related information includes DIMD flag information indicating whether a DIMD mode is applied to the current block, the TIMD-related information includes TIMD flag information indicating whether a TIMD mode is applied to the current block, and the DIMD flag information or the TIMD flag information is parsed after the MIP flag information.

Methods and apparatus for video coding. When a current intra angular prediction mode for the current block is not in the MPM list, a mode syntax related to a current intra prediction mode for the current block is signalled or parsed depending on first information derived according to DIMD or TIMD. A final intra predictor is generated based on second information comprising the first information and the mode syntax. The current block is encoded or decoded using a final mode derived based on information comprising the syntax.

A coded video bitstream is received. The coded video bitstream includes coded information of a current block in a current picture, the coded information indicates that the current block is coded by an intra prediction using an affine intra mode (AIM) model. The affine intra mode model for applying on the current block is determined. At least a first intra angular mode for a first sample in the current block and a second intra angular mode for a second sample in the current block are determined according to the affine intra mode model, the first intra angular mode is different from the second intra angular mode. The current block is reconstructed based on the intra prediction using the affine intra mode model, the first sample is predicted based on the first intra angular mode and the second sample is predicted based on the second intra angular mode.

An image decoding method performed by a decoding device includes: obtaining image information including prediction-related information from a bitstream; determining whether combined inter-picture merge and intra-picture prediction (CIIP) is applied to a current block, on the basis of the prediction-related information; deriving a prediction sample of the current block on the basis of it being determined that the CIIP is applied to the current block; and generating a reconstructed sample of the current block on the basis of the prediction sample, wherein the prediction sample of the current block is derived on the basis of an intra prediction sample and an inter prediction sample, wherein the intra prediction sample is derived on the basis of an intra prediction mode, wherein the intra prediction mode is derived on the basis of a decoder side intra mode derivation (DIMD) mode or a template-based inter mode derivation (TIMD) mode.

A video coding method using decoder-side intra mode derivation (DIMD) based on multiple histograms of gradients (HoGs) is provided. A video coder receives data to be encoded or decoded as a current block of a current picture of a video. The video coder derives a plurality of HoGs for different intra prediction angles. Different HoGs are derived based on different sets of reconstructed pixels neighboring the current block. The video coder selects a HoG from the plurality of HoGs. The video coder identifies one or more intra prediction modes based on the selected HoG. The video coder generates an intra-prediction of the current block based on the identified one or more intra prediction modes. The video coder encodes or decodes the current block by using the generated intra-prediction.

Methods and apparatuses for video decoding and video encoding and a method of processing visual media data are disclosed. The apparatus for video decoding includes processing circuitry that receives coded information indicating that a current block in a current picture is coded with a decoder-side intra mode derivation (DIMD) mode. A template of the current block includes reconstructed samples in the current picture and is adjacent to the current block. The template includes one of a left template and a top template. The processing circuitry determines a filter type from a plurality of filter types associated with the one of the left template and the top template, applies the DIMD mode to the template based on the determined filter type to determine one or more intra prediction modes for the current block, and reconstructs the current block according to the one or more intra prediction modes.

An image encoding / decoding method and apparatus, a recording medium storing a bitstream and a transmission method are provided. The image decoding method may comprise generating a derived intra prediction mode by performing decoder side intra mode derivation (DIMD) on a current block and storing the derived intra prediction mode. The current block is in a matrix based intra prediction (MIP) mode.

Methods and systems are described for intra-prediction using template matching (TM) in video coding. The proposed methods include adaptive fusion when using template-based intra mode derivation using the most probable modes (TIMD), and fusion in intra mode prediction with template matching (Intra TMP).

A video bitstream including coded information of a current block in a current picture is received. The coded information indicates a plurality of candidate intra prediction modes for the current block. Two or more predictors are determined based on the plurality of candidate intra prediction modes for the current block according to a pre-defined condition. At least one of the two or more predictors is generated based on a matrix-multiplication mode of the plurality of candidate intra prediction modes such that the at least one of the two or more predictors is obtained by a matrix multiplication of a matrix of weight coefficients and neighboring reconstructed samples in a template of the current block. The current block is reconstructed based on a weighted combination of the two or more predictors.

Methods are described for template matching (TM) in video coding. The proposed methods include: the use of constrained top and left neighbors in template matching, enabling TM only in coding tree unit boundaries, using approximated reconstructed samples, a new processing pipeline for deriving decoder side intra mode derivation (DIMD) combined with template based intra mode derivation (TIMD), and using filtered pixels from the neighbors, instead of using the reconstructed pixels. Furthermore, methods are described on how template matching may be applied in combination with Intra, sub-partitioning mode, interpolation filtering in intra prediction, block partitioning, bi-prediction with coding unit-level weights, and adaptive motion vector resolution.

Methods for video decoding and encoding, apparatuses and non-transitory computer-readable storage media thereof are provided. In one method for video decoding, a decoder may obtain a first and a second block, where the first block is coded with an Intra Block Copy (IBC) mode or an intra Template Matching Prediction (TMP) mode, and the second block is coded with the intra TMP mode or the IBC mode. Additionally, the decoder may obtain a boundary strength for a deblocking filter by applying a predefined criterion in one of an intra mode or an inter mode. Further, the decoder may apply, and based on the boundary strength, the deblocking filter on the first block and the second block.

In order to better predictively encode pixels of an image block of a video, a method of predicting a block of pixel colors of an image is proposed, comprising: determining a template-based intra mode to derive a prediction applicable to the block; determining a plurality of intra prediction modes, and determining respective costs for the plurality of intra prediction modes; determining that a first TIMD mode is a first intra prediction mode of the plurality of intra prediction modes having the lowest cost of the respective costs, and a second TIMD mode is a second intra prediction mode of the plurality of intra prediction modes having a penultimate cost of the respective costs; determining a third TIMD mode as a non-angular intra prediction mode; performing a verification with respect to the third TIMD mode being different from the first TIMD mode and the third TIMD mode being different from the second TIMD mode; forming a final TIMD mode based on the verification as true, the final TIMD mode comprising a linear combination of the first TIMD mode, the second TIMD mode, and the third TIMD mode; and forming a prediction of the block based on a template of the block and the final TIMD mode.

A device for decoding video data includes a memory and processing circuitry. The processing circuitry may be configured to determine a prediction block for a current block of the video data and determine a subsampled prediction block based on the prediction block. The processing circuitry may be further configured to apply a decoder-side intra mode derivation process to the subsampled prediction block to determine an equivalent intra mode for the current block. The processing circuitry may also be configured to determine a decoded version of the current block based on the equivalent intra mode and output a picture of decoded video data comprising the decoded version of the current block.

An apparatus (e.g., which may be an encoder or decoder) may be configured to determine that direct mode (DM) prediction is applicable to a first chroma block. For a first chroma block, the apparatus determines that an associated first luma block is encoded with one of Intra Block Copy (IBC) and Intra Template Matching (IntraTMP). The apparatus determines a reference block associated with the first luma block and intra information associated with the reference block. The reference block associated with the first luma block may have been used to process the first luma block. The apparatus determines a vector associated with the first luma block, and determines the reference block and intra information associated with the reference block based on the vector. The apparatus determines a first intra mode associated with the reference block, and performs prediction of the first chroma block using the first intra mode associated with the reference block.

A method of configuring candidate intra modes and a video decoding apparatus are disclosed. At least one embodiment of the present disclosure provides a method of configuring candidate intra modes for a chroma block, including determining whether a luma region corresponding to the chroma block has an encoding mode that is available for use, setting a direct mode (DM) among the candidate intra modes as a default mode when the encoding mode of the luma region is not available, and configuring the candidate intra modes by including the DM.

Encoding of geometric prediction modes with template matching is implemented with embodiments of improved encoding and decoding. In one embodiment, the intra mode index and the partition mode are collectively encoded, allowing the uniquely generated index to be classified and the index with less cost to be encoded over a shorter code length. In another embodiment, classification of intra prediction modes of allowed intra geometric partition modes is based on template matching costs, so that the cheapest mode is encoded with fewer bits.

An example device for decoding video data includes a memory configured to store video data; and a processing system comprising one or more processors implemented in circuitry, the processing system being configured to: generate a prediction block for a current block of video data using a neural network; determine an equivalent intra mode for the prediction block from a set of available intra-prediction modes using decoder-side intra mode derivation (DIMD), the equivalent intra mode representing one of the intra-prediction modes that would generate an intra-prediction block that would best match the prediction block generated using the neural network; decode a residual block for the current block of the video data based on the equivalent intra mode; and combine the prediction block with the residual block to decode the current block of the video data.

A method and an apparatus for encoding or decoding an image or a video are provided wherein, for at least one block of a video, at least one histogram of angular intra modes occurrences is obtained. For at least one angular intra mode, a bin value for the at least one angular intra mode in the at least one histogram depends on determining whether or not the at least one angular intra mode is mappable to a matrix-based intra mode. A prediction block for the block is determined based on an intra prediction mode that uses the at least one histogram, and the block is encoded or reconstructed using the prediction block.

Aspects of the present disclosure include methods and apparatus for video decoding and encoding, and methods of processing visual media data. A method for video decoding includes receiving encoded information in a bitstream, the encoded information indicating that a first intra mode coding method is not enabled for a current block, the first intra mode coding method using one of (i) template-based intra prediction mode derivation (TIMD) and (ii) decoder-side intra mode derivation (DIMD). The method for video decoding includes: determining at least one template-based intra mode using a first intra mode coding and decoding method using one of TIMD and DIMD; and when the at least one template-based intra mode is excluded from the second intra mode codec method, determining an intra prediction mode of the current block using the second intra mode codec method excluding the at least one template-based intra mode, and reconstructing the current block using the intra prediction mode.

An image decoding method according to an embodiment of the present invention may comprise the steps of: configuring a template region including reconstructed pixels adjacent to a current block; obtaining directionality information by applying a gradient filter to the pixels in the template region; generating a histogram for multiple intra prediction modes on the basis of the directionality information; performing adaptive processing on the basis of characteristics of the histogram; generating a prediction block for the current block by using at least one intra prediction mode selected from the histogram; and reconstructing the current block by using the prediction block, wherein the step of the generating of the histogram includes generating the histogram through matching between a calculated angle and the intra prediction mode, and the step of the performing of the adaptive processing includes at least one of early terminating additional gradient analysis when the count of a specific mode exceeds a first threshold value, and expanding the template region or selecting a non-directional prediction mode when the count of all modes is less than a second threshold value.

A method of coding implemented by a decoding device, comprising obtaining a video bitstream; decoding the video bitstream to obtain an initial intra prediction mode value for chroma component of a current coding block; determining whether a ratio between a width for luma component of the current coding block and a width for chroma component of the current coding block is equal to a threshold or not; obtaining a mapped intra prediction mode value for chroma component of the current coding block according to a predefined mapping relationship and the initial intra prediction mode value, when it's determined that the ratio is equal to the threshold; obtaining a prediction sample value for chroma component of the current coding block according to the mapped intra prediction mode value.

A video encoding / decoding method and apparatus are provided. The video decoding method relating to this disclosure includes the steps of: acquiring one or more candidate intra-prediction information based on intra-prediction information of surrounding blocks of the current block; constructing an intra-prediction candidate list based on the one or more candidate intra-prediction information; acquiring an intra-prediction candidate index indicating one of the candidate intra-prediction information included in the intra-prediction candidate list; and generating a predicted block of the current block by performing intra-prediction based on the candidate intra-prediction information indicated by the intra-prediction candidate index. The candidate intra-prediction information includes TIMD (Template based intra mode derivation) information, DIMD (Decoder side intra mode derivation) information or linear model information, LIP (Linear interpolation intra prediction) information, PDPC (position dependent intra prediction) information, MRL (multi reference line) information, TMRL (Template-based multiple reference line) information, ISP (intra sub-partition) information, MIP (matrix-based intra prediction) information, interpolation filter information, MDIS (mode dependent intra smoothing) information, and CIIP (combined inter and intra It may include at least one of the following: prediction information, SGPM (spatial geometric partition mode) information, intra-TMP (template matching intra prediction) information, in-screen prediction directionality mode information, extended planar information, intra-prediction fusion information, peripheral reference sample characteristics information, or IBC (intra block copy) information.

Decoding using compound warp inter-intra prediction includes obtaining reconstructed block data for a current block. Obtaining the reconstructed block data includes accessing, from an encoded bitstream, compound warp inter-intra mode data indicating that the current block is coded using compound warp inter-intra mode, accessing, from the encoded bitstream, intra prediction mode data indicating an intra prediction mode for the current block, generating intra prediction block data for the current block in accordance with the intra prediction mode data, generating warp inter prediction block data for the current block, obtaining predicted block data for the current block by combining the warp inter prediction block data and the intra prediction block data, obtaining decoded block data by decoding encoded block data accessed from the encoded bitstream, and including, in the reconstructed block data, a sum of the decoded block data and the predicted block data.

Provided are a video decoding method and a video decoding device, which, during video encoding and decoding processes, obtain most probable mode (MPM) information indicating whether to use MPMs of a current block determined based on at least two of a prediction mode of a left neighboring block adjacent to a left side of the current block, a prediction mode of an upper neighboring block adjacent to an upper side of the current block, and a right neighboring block adjacent to a right side of the current block, obtain extended intra mode set information indicating whether to use an extended intra mode set configured based on the MPMs, and determine an intra prediction mode of the current block based on the MPM information and the extended intra mode set information.

A method and apparatus for generating an extended MPM (Most Probable Modes) list by adding the target DIMD candidate and said at least one neighbouring mode of the target DIMD candidate to an initial MPM list. A target DIMD candidate is determined for the current block based on a DIMD process using statistics or histogram of angle field derived from a template of the current block. At least one neighbouring mode of the target DIMD candidate is generated by adding an offset to a corresponding mode number of the target DIMD candidate, and wherein the offset corresponds to a non-zero integer. An extended MPM (Most Probable Modes) list is generated by adding the target DIMD candidate and said at least one neighbouring mode of the target DIMD candidate to an initial MPM list. The current block is encoded or decoded using information comprising the extended MPM list.

A method for predicting a current block in a video using overlapped block intra prediction is provided, the current block being intra-coded, the method comprises obtaining a first prediction block using an intra mode determined for the current block, obtaining at least one second prediction block using a prediction mode determined for a neighboring block of the current block, and predicting the current block using an overlapped block intra prediction blending using the first prediction block and the at least one second prediction block for at least a part of the current block. Methods for encoding or decoding the current block based on the predicting are also provided as well as corresponding apparatuses.